Whey protein concentrates are well known materials in the prior art. These materials have been prepared by various means which effectuate the removal of the valuable whey protein from the millions of gallons of whey produced in this and other countries of the world per year. As more and more companies attempt to isolate this protein, more and more uses for the product have to be found. This is particularly important since the less expensive dry whey and delactosed whey can compete in various market areas that were originally held by whey protein concentrates.
The use of a whey protein concentrate as a replacement for non-fat dry milk in baked goods is set forth in U.S. Pat. No. 3,941,895. The prior art has not been able to put this invention into commercial practice since the cost of the whey protein concentrate far exceeds the cost of the non-fat dry milk constituent being placed. The only advantage that can be gained by using such a direct substitution would be in the preparation of baked goods having a high protein content.
One of the other areas of use of whey proteins has been in the area of whipping agents. Because of the similarity of the classes of proteins between egg albumen and whey proteins, a logical extension was to utilize whey proteins as a substitute for egg albumen or its functions. Numerous attempts have been made to interest various commercial organizations in utilizing whey protein concentrates as substitutes for egg albumen in baked goods as whipping agents and the like. However, the replacement of egg albumen with whey protein concentrates has not always been satisfactory. It is known that the use of a highly concentrated whey protein concentrate can be effectively used. Commercially, the processing steps needed to prepare the material would not make the substitution economical. Commercially available whey protein concentrate such as an ultrafiltered whey containing 50% protein will not effectively replace large amounts of egg albumen in cakes, even though an economic advantage could be gained by using the less expensive whey protein concentrate as a substitute for the albumen. The cakes so produced evidence lower cake volume, especially at a weight/weight replacement of albumen with concentrate and weaker texture particularly when albumen replacement is above 50%. Testing has shown that in general, only small amounts of egg albumen, i.e., up to 25%, can be replaced with the whey protein concentrate. Such use has not heretofore been considered to be generally commercially successful.
It has also been disclosed that a whey protein/carboxymethylcellulose (CMC) complex is useful as a substitute for eggs. This is described in the article "Studies on the Formulation of Egg Substitutes from Milk Protein Complexes for use in Caking Making", by R. S. Mann et al. (National Dairy Research Institute, Karnal India) Journal of Food Science and Technology, Volume 12, Nov. 5, September-October, 1975 (pp. 241-244). The complex used in the study was obtained according to the methods of Hidalgo and Hansen, Journal Agric. Fd. Chemistry, 1969, 5 p. 1087. Hidalgo et al. disclose forming a complex between beta-lactoglobulin and carboxymethylcellulose (CMC) by treating the protein with the CMC at an acid pH of about 4, an ionic strength of below about 0.1 and a ratio of CMC to protein of 0.25-0.50.
Hidalgo et al. teach that further addition of CMC caused resolubilization of the complex. They also teach that solutions of beta-lactoglobulin and CMC at pH 7 provided no complex. The complex formation is taught to occur through two separate reactions, a primary interaction which leads to the formation of insoluble complexes and a secondary reaction which solubilizes the complex.
It is also known that beta-lactoglobulin can be selectively complexed from whey by the method of Hidalgo et al. (See Selective Precipitation of Whey Proteins with Carboxymethylcellulose, Hidalgo and Hansen, Journal of Dairy Science, Volume 54, No. 9, September 1971, pp. 1270-1274). By treating whey with CMC at pH 4, a complex containing beta-lactoglobulin and bovine serum albumin can be separated. The alpha-lactalbumin can be complexed and removed from the supernatant by reaction with CMC at pH 3.2. The proteose-peptones remaining in the supernatant can be coprecipitated with calcium phosphate by raising the pH of the final supernatant to 7.5.
The use of CMC to form a CMC/beta-lactoglobulin complex which is useful as an egg substitute in cakes requires a specific reaction sequence which leaves the remaining whey proteins in solution. Further, only specific amounts of CMC can be effectively used to form the complexes. The amount of whey protein used as the egg substitute substantially dictates the amount of CMC which is present in the final product.
It has now been found that an egg albumen and egg substitute can be formed which overcomes the difficulties of using whey protein per se as well as the difficulties in forming a beta-lactoglobulin/CMC complex.